[emeritus]

My recollection is that polythene/polyethylene and polypropylene have a soapy feel and by their nature cannot be glued or bonded. Something to do with the molecular structure. I think that plastics of these types were used in some of my children's toys, and when they broke I had to mend them using mechanical fastenings such as wire, small rivets or screws as nothing would stick to them. Possibly the radio case would be ABS or Polystyrene in that era, which can be mended using solvents or epoxy adhesives. I remember that the Polyclens paint brush cleaner that was around circa 1960 could be used for assembling Airfix kits as it dissolved polystyrene. Where a pillar needs some extra support, or part of it is missing, I use Plastic Padding. Plastic Padding seems hard to come by these days, so I use Ronson wood filler, which seems to be much the same product.

Edit: crossed with Herald!